The electrochemical formation of diaryliodonium salts is known for benzene plus iodobenzene (see Wendt: H. Hoffelner, H. W. Lorch, H. Wendt, Journal of Electroanalytical Chemistry, 66 (1975), pp. 183-194) and toluene plus iodobenzene (see Miller: Larry L. Miller, A. K. Hoffman, JACS, 89 (1967), pp. 593-597) using platinum electrodes, divided cells, acetonitrile solvent and perchlorate electrolyte. In both cases these do not represent commercially feasible sets of conditions. Divided cells are more expensive to operate due to additional voltage drop in the cell. Platinum is too expensive for anode material on a commercial scale. In addition, there is no report of a regioselective system in this prior art which can be important for some applications.
Other prior art of interest includes U.S. Pat. No. 4,759,833 which discloses the simultaneous preparation of a diaryliodonium salt and an alkoxide salt using a divided cell. The only anode taught in this patent is platinum.
Diaryliodonium salts have a variety of uses such as photoinitiators (U.S. Pat. Nos. 4,136,102 and 3,981,897), fungicides (U.S. Pat. Nos. 3,944,498 and 3,763,187) and bactericides (U.S. Pat. Nos. 3,885,036 and 3,712,920). Thus, it would be desirable to have a more economically and industrially feasible process for preparing such compounds.